Archery bows typically have a pair of pulleys, with at least one of the pulleys having a cam surface to provide a mechanical advantage in drawing a drawstring of the bow. Archery bows having a pulley arrangement are commonly referred to “compound bows”. Typically, a user purchases a compound bow having the desired draw length that suits their physical size. To adjust the draw length of a compound bow, typically the user must seek assistance from an experienced technician to install the proper length draw string and/or pulley having the desired characteristics to provide the desired draw length. This often limits the offering of bows a purchaser has to choose from, and also proves inconvenient in having to seek out assistance from an experienced technician to install the proper length draw string and/or change the pulley or cam.
In addition, the user must also select a bow having a suitable range of draw weight to accommodate the user's strength and ability to draw back the drawstring. Typically, compound bows have a pair of bow limbs attached to a riser with a pair of limb bolts. To adjust the draw weight of the bow, it is known to provide a limited amount of adjustment by loosening the bolts to decrease the draw weight, or tightening the bolts to increase the draw weight. Typically, adjustment of the limb bolts allows for a draw weight adjustment over range of 10. Though the draw weight may be adjusted by tightening and loosening the limb bolts, compound bows typically operate most efficiently when set near the upper limit. Loosening the limb bolt also reduces the number of threads securing the limb bolt to the riser. As such, users are typically best suited if they purchase a compound bow having an upper limit close to their desired draw weight. As such, though the user may have the ability to adjust the draw weight by almost 10 pounds, practically speaking, the user typically maintains the bow towards the upper end of the draw weight limit to achieve maximum efficiency and performance of the bow. Otherwise, to obtain a draw weight outside the range of adjustment of the limb bolts, other changes to the bow must be made, such as switching the limbs having different stiffness, and/or changing the cam pulley or pulleys. These changes require the assistance of an experienced technician and a bow press.
Further, compound archery bows typically have one pulley or cam providing for guided entrainment of a bow string at least in part over three laterally spaced planes.